The magical material, graphene, once again surprises scientists with its own special "transformation" function. According to a report from the Physicist Organization Network on August 13, a research team at the Massachusetts Institute of Technology (MIT) found that when placing graphene sheets on different substrates, their basic properties, such as conductivity and chemistry with other substances The effect, etc., may change significantly depending on the nature of the base material. The research results were published this week in the journal Nature and Chemistry.
Because graphene is only one atom thick, scientists often put other materials under its support in practice. When the material being covered is silica commonly used in the electronics industry, graphene can be easily “given a specific function†when it comes into contact with certain chemical substances; but if the supporting material is replaced with boron nitride, the The same chemical, it has almost no chemical reaction.
"This is very counterintuitive," said Michael Stellano, a senior author of the research paper and a professor at the Massachusetts Institute of Technology's Department of Chemical Engineering. "You can turn off and open graphene to form chemical bonds based on the substrate material."
The researchers found that graphene changed its properties because it was too thin and the reaction pattern was strongly influenced by the electric field of atoms in the underlying material. This means that a device can be fabricated by overlaying a lithographic pattern substrate with a layer of graphene. A portion of the lithographic pattern substrate is silicon dioxide and the other is a boron nitride coating. The chemical behavior of the graphene will be based on Hidden patterns change.
Wang Qinghua, a postdoctoral fellow at the Massachusetts Institute of Technology and the lead author of the paper, said: “You can interact with different molecules of a biomarker (these areas on the graphene surface) without destroying the biomolecules themselves.†Assist in the fabrication of microarrays for sensors that detect trace amounts of biological or chemical substances because most current techniques for making such patterned surfaces involve the use of high temperatures and reactive solvents that can destroy these sensitive biomolecules.
Strano said that graphene can even eventually become a protective coating for many materials. For example, when it is bonded to copper, it can completely eliminate the metal oxidation of copper and protect it from corrosion.
Strano said that many chemists are puzzled by the seemingly unpredictable reactions of graphene under different conditions. They proposed this new theory of electron transfer and explained the behavior of graphene as a substrate material. Influencing, this new understanding can also be used to predict the properties of graphene on other substrate materials. Wang Qinghua also believes that other research teams can gain inspiration, explore more base materials, and try to optimize the performance of graphene.
James Turle, professor of chemistry and computer science at Rice University, said: “This is the first systematic study on the effect of substrate materials on the chemical reactivity of graphene. It is very well-conducted and the results are convincing.†(Reporter Chen Dan )
Bearing Ball,Self Aligning Ball Bearing,Steel Ball Bearings,Self Aligning Bearing
Dongyang City Shuangchi Bearing Co.,Ltd , https://www.zjscbearing.com